Some causes of underarm rash include infection, allergic reaction, and inflammation. Itchy, inflammatory, bacterial, or fungal rashes in your armpit can be mild or severe, short-lived or chronic.

The same condition that causes dandruff -- seborrheic dermatitis --also can cause a red and itchy beard. AndreyPopov Getty Images/iStockphoto If the skin under your facial hair is often red, irritated ...

A rash or skin irritation can develop anywhere that skin folds exist on the body. These folds can trap heat, moisture, bacteria, and yeast. Combined with chafing, this leads to a condition called ...

Dear Doctors: I have dandruff, and my doctor says it’s from seborrheic dermatitis. Can you explain what that is? I’ve been using the special shampoo I was given, and it helps. When I stop using it, ...